This proposal has two objectives: [1] to complete a 15-year longitudinal study of textile workers in Shanghai, China, and [2] to examine a naive population of textile workers at entry and during the first three years of employment. This proposal is designed to address unanswered questions regarding the respiratory health of workers chronically exposed to organic dust and endotoxin. Exposure to gram-negative bacterial endotoxin has been described in laboratory studies as producing acute respiratory symptoms and lung function change. Similar observations have not been reproduced in actual mill settings. To date, no other prospective epidemiologic study has addressed the relative contributions of cotton dust and endotoxin in producing both acute and chronic respiratory effects. The importance of endotoxin in causing pulmonary effects is important not only in Inc cotton textile industry, but also in a number multitude of other environments where significant levels of airborne endotoxin are encountered. The first objective is focused on a study population that has been followed since 1981 and is unusually well-suited for epidemiologic study due to: low turnover, very low smoking prevalence among women workers, reliable baseline data, a suitable comparison group studied in identical fashion, excellent cooperation among industry officials, union and the collaborative'. research team, access to subjects who have retired or left the industry in disability, and cost-efficiency. The population includes a closed cohort of 447 cotton textile and 465 silk textile workers first surveyed in 1981. Follow-up surveys were conducted in 1986 and 1992 with 90% success. The proposed study is unique because exposure estimates for both dust and endotoxin over a 15-year period allow assessment of exposure-response relationships for both dust and endotoxin for the full study interval. To address the second objective in this renewal application, we propose to expand the study - beyond the original cohort and recruit 400 subjects naive to mill exposures. We have a rich opportunity to access and test volunteers who have been hired, but not yet exposed to cotton dust in order to determine early responses that may be markers of risk for leaving the job and for developing chronic respiratory disease. This opportunity exists because the Shanghai Textile Industry's employment practices are unique. We will recruit 2()() cotton and 200 silk newly-hired workers, assess their pre-exposure for bronchial responsiveness, atopy and baseline respiratory health. We will then follow them closely for the first 3 years of employment with symptoms, pulmonary function (cross-shift) and dust/endotoxin measurements.